The statistics, released last month, represent only the crimes people tell police about. Some number go unreported, and experts caution against drawing too strong a conclusion from a year-to-year change.

Through 2011, reports of violent crime in Anchorage had decreased for three years running, and property crimes had dropped the previous two years.

Still, Deputy Chief Steve Hebbe said in an interview that the across-the-board rises have the department's attention.

"That definitely has us looking at it as probably less of an anomaly, and maybe more indicative of what could be the start of a trend," he said.

A spokeswoman for Mayor Dan Sullivan disagreed, saying in a written statement that "one higher crime year doesn't produce a four-year trend."

"Over the course of this administration the numbers have been lower, and there were fewer crimes reported during 2011 than 30 years ago," said the spokeswoman, Lindsey Whitt.

In a brief interview Tuesday evening, Sullivan said he had discussed the numbers with Chief Mark Mew, but had not yet seen the detailed figures.

He said that he was awaiting further analysis before considering any changes in policy, but emphasized the previous years' declines.

"Our overall average is good," he said. "We don't particularly let one year, as an anomaly, change what we're doing."

Hebbe, who spoke while Mew was away on vacation, said the department has seen "a trend towards more violence, just in general."

The total number of violent crimes reported in 2012 -- murders, rapes, robberies and aggravated assaults -- was 2,479, up from 2,388 in 2011, according to the FBI.

While reported property crimes saw a larger jump, to 10,543 from 9,455, Hebbe said those numbers tend to fluctuate more. Over the past several years, reports of property crimes have risen and fallen by as much as 1,900 annually.

Hebbe also pointed out that while the number of reported rapes rose from 283 to 303, the counts aren't necessarily analogous, since the FBI broadened its definition of the crime last year.

Hebbe said the department was trying to combat the rises through data-driven policing, and by using tactics like aggressive traffic enforcement in high-crime areas.

The numbers come as the police department's staffing levels fell, from 390 officers in 2011 to 372 in 2012, according to the FBI report.

Mew previously said he expects the department to keep shrinking next year, likely hovering between 335 and 350 officers. He said he would like the total at 374 or 375.

In an interview last week, Sullivan had said he is focused on results, not staffing, and pointed to the FBI statistics through 2011, without mentioning the newly available 2012 numbers.

Whitt, however, pointed to Sullivan's State of the City speech last month, which included a PowerPoint presentation that said the 2012 statistics were "trending upwards" and were still being analyzed.

She said that Sullivan "doesn't believe that there is a direct correlation with police staffing numbers and crime statistics."

That's a view echoed by Hebbe, who acknowledged that more officers on the street could drive up the numbers by catching more criminals, or down by deterring bad behavior.

"You can prove almost any point you want to make with the stats," he said.

Derek Hsieh, the president of the city's police union, acknowledged that it can be "very dangerous" to look at differences over just one year. But he also said that rising numbers across the range of crimes are cause for concern.

"We're seeing increases in every category, and they're not minor," he said. "In conjunction with reduced staffing, which would indicate lower reported crime, we have problems."

Police departments should respond to shifts in crime over a longer period than just one year, and they should also find ways to account for crimes that go unreported, said Brad Myrstol, a criminologist and University of Alaska Anchorage professor.

People report crimes at different rates, and the disparities can be captured by surveying the public, he said. Those in turn can be combined with the FBI numbers to give police a more comprehensive view of what's happening on the street.

"You want to develop policies that aren't designed to respond to false positives in terms of the volume and direction of crime," Myrstol said. "It's really important to understand the context of crime."